The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

Three dead on NSW roads on Anzac weekend

Three men have died in separate NSW accidents on the final day of the Anzac Day long weekend, with police booking more than 2800 motorists for speeding and other offences over the three days.

A 25-year-old man died about 10.30am (AEST) on Sunday when he lost control of his car and hit a pole on Kanangra Drive at Gwandalan on the Central Coast.

The sole occupant died at the scene with police believing wet weather was a factor.

A man died when his motorbike and a car collided at Sanctuary Point on the state's south coast about 4pm. The driver of the car was not injured and was taken to hospital for mandatory blood and urine testing.

The third fatality occurred at Burrabadine, near Dubbo, just before 5pm when a car left the road and hit a tree.

Police said his death took the Anzac Day long weekend toll to five.

They said the holiday road safety blitz, Operation Go Slow, resulted in 2412 people being charged with speeding offences, while 333 drivers were issued tickets for driving unrestrained and 94 were caught for drink-driving offences.

Four men were charged with drug offences after officers allegedly found an amount of cannabis, amphetamine and ecstasy during a random breath test on Saturday in Temora, about 50km northwest of Cootamundra.

The 19-year-olds were granted bail to appear at Wagga Wagga Local Court on Wednesday June 4.